This previously unpublished journal provides an eyewitness account of the epic chase of the USS Essex that was the inspiration for the film Master & Commander. In 1813 the British frigate Phoebe set out on a secret mission to counter the campaign by the frigate USS Essex, which had almost annihilated the lucrative British whaling trade in the south Pacific. After an epic voyage and a nerve-wracking rounding of Cape Horn, Phoebe tracked her prey to neutral Valparaiso where the American frigate was blockaded. A cat-and-mouse game that lasted months ended with an attempted break-out and a bloody battle in which Essex was captured.